html,
body{
    margin: 0;
    padding: 0;
}
.box{
    display: flex;
    height: 100vh;
    width: 100vw;
    justify-content: center;
    align-items: center;
    background: url(./image/login.jpg) fixed no-repeat;
    background-size: cover;
}
.login_form{
    display: flex;
    position: relative;
    width: 240px;
    height: 220px;
    /* 将元素纵向展示 */
    flex-direction: column;
    padding: 40px;
    text-align: center;
    /* 继承父元素的属性 */
    background: inherit;
    border-radius: 18px;
    overflow: hidden;
    z-index: 100;
}
/* 背景图片局部模糊模糊区域 */
.login_form::after{
    content: "";
    position: absolute;
    top:-10px;
    left: -10px;
    width: calc(100% + 20px);
    height:calc(100% + 20px);
    border-radius: inherit;
    box-shadow:inset 0 0 0 6px rgba(255,255,255,.25); 
    background: inherit;
    z-index: -1;
    filter: blur(6px);
    overflow: hidden;
}
.login_form h2{
    font-size: 18px;
    font-weight:400;
    color: #3d5245;
}
.login_form input,
.login_form button{
    margin: 6px 0;
    height: 30px;
    border: none;
    border-radius: 4px;
    background-color: rgba(255,255,255,.3);
    color: #3d5245;
    outline: none;
}
.login_form input::placeholder{
    color: #3d5245;
}
.login_form button{
    /* position: relative; */
    margin-top: 24px;
    background-color: rgba(41, 124, 73, 0.2);
    color: white;
    overflow: hidden;
    cursor: pointer;
    transition: all 0.6s;
    
}
.login_form button:hover{
    background-color: rgba(41, 124, 73, 0.5);
}